Silicon is pretty expensive these days, and traditional solar panels need a lot of it to convert light to energy. But two of the great opportunities for expansion in solar is using less silicon, by concentrating light on smaller panels, and increasing efficiency by tilting panels to follow the sun. These roof-mounted units created by Soliant Energy (Soliant Green Energy?) do both of those things, with no external power equipment necessary.

The innovation here is called the ‘heliotube.’ It’s a tube of glass that concentrates the sun’s rays onto a very thin strip of silicon solar panels at the base of the tube. The tube is then connected to a frame in blocks, and the frame uses the power coming off the panel to tilt the tubes to track the sun. These panels use 88% less photovoltaic material, but are almost as efficient per square foot as traditional solar panels.

While it would be more efficient if the panels could tile vertically as well as horizontally (and thus track the exact path of the sun) the simple design and ease of installation will bring the intial costs of these panels way down. Right now, this initial cost is basically the barrier that keeps solar power from juicing high-sunlight areas of the world.

Unfortunately this design has a few flaws. Currently, the troughs placement causes them to occasionally shade each other, preventing them from capturing the maximum amount of sunlight. However, the next revision hopes to correct the former problem by breaking up the rows into sections so that they can follow the sun in every direction.

They estimate an eventual improvement of energy production by 300% from their current design. The panels are scheduled to ship this year, with the new model having an estimated 2010 completion date.